#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int main()
{
	int a = 1, b = 1, c = 1;
	while (scanf("%d %d %d", &a, &b, &c) != EOF)
	{
		if (a + b > c && a + c > b && b + c > a)
		{
			if (a == b && b == c)          printf("Equilateral triangle!\n");

			else if (a == b || a == c || b == c) printf("Isosceles triangle!\n");

			else  printf("Ordinary triangle!\n");
		}
		else     printf("Not a triangle!\n");
	}
	return 0;
}
